Sen. Sherrod Brown (D-Ohio) is being sued by an Ohio business owner who says a campaign ad makes false and defamatory claims against him because he supports Brown’s opponent, GOP Rep. Jim Renacci, according to The Columbus Dispatch.

Benjamin Suarez, owner of SCI Industries in Jackson Township, Ohio, filed the lawsuit Thursday in a Stark County court, pushing back against a claim that he is a “crooked businessman.”

“Suarez is not a ‘crooked businessman,’ Representative Renacci did not use his office to try to get a lawsuit dismissed against Suarez, and Suarez did not send $100,000 to Representative Renacci,” the lawsuit says.

An advertisement by the Friends of Sherrod Brown campaign strongly implied that Suarez sent Renacci $100,000 in exchange for Renacci using his influence as a congressman to resolve a lawsuit against Suarez.

According to The Columbus Dispatch, Mandel and Renacci returned the donations, and Suarez claims donations were not related to him reaching out to Renacci for help with his lawsuit.